For good oral hygiene, it is essential that deposits on the teeth be removed as often as possible. The deposition of material called "plaque" on the teeth is a two-stage process which is not entirely understood. Initially, an amorphous, non-bacterial layer is laid down composed of "pellicle", a thin film made up chiefly of an organic keratin-like substance. This is followed by a bacterial invasion and subsequent bacterial proliferation. It is generally thought that tooth decay is caused by certain types of these bacteria. Acidogenic bacteria within the plaque feed on sucrose in the diet producing acids which decalcify the teeth allowing the underlying areas to be destroyed. The plaque assists by holding these acids near the tooth surface. If not removed, the plaque will harden into calculus. If this plaque is regularly removed, the incidence of caries formation can be greatly reduced. Such deposits also contribute to halitosis, commonly known as bad breath.
A simple and effective way to remove deposits is by the use of a toothbrush or similar device. However, it is not always convenient to brush or carry mouthwash. While various dissolving tablets, breath drops, and sprays may be used for controlling bad breath, they only mask the problem, rather than removing its cause. Moreover, they do nothing to prevent decay, and in fact, some actually promote it, because the sucrose sugar incorporated as part of a tablet or lozenge may deposit as film on the teeth as the tablet dissolves. Such tablets also typically incorporate a sialagogue to stimulate the flow of saliva which helps to remove food particles from the teeth. However, this is only effective for loosely-held deposits and does little for those more stubbornly held.
Various types of chewing gums have also been suggested for use when it is inconvenient to brush. However, chewing gums do not have the rigidity needed for cleaning. This means that most of the film or plaque removal occurs on the biting surfaces of the teeth with very little, if any, on the buccal areas.
The addition of various abrasives to a gum base is suggested in U.S. Pat. Nos. 3,422,184 and 3,297,452, as a means for better cleaning the teeth. However, any gum base will fall short of effective cleaning since forces applied to the gum base result in deformation of the gum base, reducing the force actually applied to the surface of the teeth. This is true to a varying degree regardless of whether the gum base is chicle, gum acacia, as suggested in U.S. Pat. No. 3,422,184, or silicone polymer as suggested in U.S. Pat. No. 3,297,452.
The present invention overcomes the above problems by providing a chewable tooth cleaning device combining chewing properties similar to the prior art compositions with the added rigidity, shape, and surface properties necessary to effectively clean teeth.